Crap (well good, depends on how you look at it). I think you are right.
I combined two decks with 2 different presets (9.75% and 5.72% RMSE each).
I put them under the same preset and it turned to have lower RMSE than both!
On one hand, I am happy that I have found a probable cause.
On the other hand, I am distraught because now I think I have ***** myself over. And I don’t know how to fix this mess.
I have 240+ different presets and hundreds of decks.
I don’t know which preset combination is the best and what is the best number of cards in a deck for it to have a preset
Now this really starts to make sense.